Finding the Fourth Proportional to 1,665.76, 2,496.57 and 690.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,665.76 : 2,496.57 = 690.88 : x
2. Step 2: Convert to fraction form
   1,665.76/2,496.57 = 690.88/x
3. Step 3: Cross multiply
   1,665.76x = 2,496.57 × 690.88
4. Step 4: Simplify right side
   1,665.76x = 1,724,830.28
5. Step 5: Solve for x
   x = 1,724,830.28/1,665.76
6. Step 6: Final answer
   x = 1,035.46